Bebtalan dtts chnitz



B. ouscnwnz. ARRANGEMENT FOR FORMING ELECTRICAL ARCS. APPLICATION FILED JULY 14, I9II. RENEWED JULY 22, I918.

Patented May 20, I919.

BERTALAN DUSGHNITZ,

OF BERLIN, GERMANY.

ARRANGEMENT FOR FORMING ELECTRICAL ARCS.

Specification of Letters Patent.

Application filed July 14, 191 1, Serial No. 638,509. Renewed July 22, 1918. Serial No. 246,229.

To all whom it may concern:

Be it known that I, BERTALAN DUsoHNITz, engineer, citizen of the Kingdom of Hungary, subject ofthe King of Hungary, residing at Berlin, in the Empire of Germany, have invented new and useful. Improvements in Arrangements for Forming Electrical Arcs, of which the following is a specification.

This invention relates to arc lamps having electrodes which are conductors in the cold state and burn in the air.

The object of the invention is to produce an are without moving the electrodes, by forming abridge of hot conducting particles and vapors between the electrodes. This is accomplished by highly heating between the live electrodes such which when heated emit finely divided conducting particles and conducting vapors; these substances being insulated from. one or both electrodes, for instance by an air space.

The substances serving to produce the conducting bridge which causes the arc may be of a very difl'erent nature; all that is essential is that when sufliciently warmed they will divide wholly or partially into fine particles which, either on account of the heat or by chemical or electric effects, are shot out from the heatin point in various directions as if by an expl bsion. The products of ex plosion may be solid, liquid or gaseous. Suitable substances for this purpose are for instance metals, and other conductors which are combustible at the temperature which is to be attained; other substances which may .be employed, comprise combinations of conductors with non-conductors such for instance as conductors in the form of carbon, graphite, metallic powder and the like mixed with n0n-conductors in the form of gypsum, metal oxids, earth alkalis, cellulose products, gum-arabic and the like.

The means for heating the substances may be of any kind in so far as the temperature reached by it is suflicient to cause the quick disintegration or decomposition of the substance lying between the electrodes. Electric means are the most suitable for this, especially resistance heating. For heating the explosive substance, said substance can be connected with a conductor of relatively great resistance in such a manner that, as soon as a current is sent through this conductor, the explosive substance is heated Y are.

substances,

, sive substance after the and the disintegration takes place. The explosive substance may itself entirely or partly effect the conduction of the current used for heating. In this case it is best to arrange the point of the greatest resistance at the point where the explosion is to occur.

If the starting of the arc is to take place successively any number of times it must be arranged so that it is possible to repeat the explosion. The explosive substance may then. not be destroyed "by a single explosion but must 'be of such a nature that it is only decomposed by the explosion while the heating temperature is maintained and the heating must last onlyduring the ignition of the This is attained by weakening or switching off the current which indirectly or directly causes the heating of the explo arc is started. This weakening or switching off of the auxiliary current used for heating may take place electrically.

The conductor of the auxiliary current which serves to heat the explosive substance is suitably arranged so'that it leads to the starting points of the are which is to be formed. This conductor may form the explosive substance and consist of metallic wire for instance copper. The auxiliary current conductor leads into the vicinity of the burning ends of the electrodes, and connects the various imaginable roots of the arc to be formed in the course of the consumption of the electrodes, that is to say it leads preferably along the electrodes, to an extent which corresponds to the length of consumption.

The heating of this wire near the roots of the arc may be efiected by the aid of a conducting mass of a high resistance placed between the wire and the electrode and'establishing the contact with it. The wire is in this case insulated from the resistance mass at all points with the exception of the point of contact by means of a combustible insulation.

In order better to understand the essential Patented May 20, 1919.

points of the invention a constructional bons one after another, so that when one pair of carbons is consumed the next is cut in automatically and one only burns always.

In the constructional form shown a group of glow lamps h, h is used as series resistance, as the arrangement according to the invention permits electric glow lamps to be immediately switched into the circuit of the arc lamps. This was impossible with the processes hitherto known for forming are because of the sudden change in the strength of the current which takes place with the ignition arrangements which have been hitherto usual and which are based on the principle of short circuit between the electrodes. In my arrangement the current passes through theglow lamps only after the arc is formed, as the arc is here a part and simultaneously a series resistance of the circuit in which the glow lamps lie.

In the accompanying drawings Figure 1 represents a longitudinal section partly in' elevation of an arc lamp embodying this invention;

Fig. 2 represents a diagrammatic section through the electrodes of Fig. 1 with the other parts of the lamp shown diagrammatically. I

Fig. 3 is a perspective View of the lower electrode of the lamp.

Fig. 4 is a longitudinal sectionof a portion of the electrodes shown in Fig. 1' on an enlarged scale.

The current enters the apparatus at f, and the wire f branches oil at the point p and leads on one side through the glow lamps h and the main current switch coil E simultaneously to the three upper carbons e of the same polarity. The other branch of the wire f, namely the auxiliary current conductor 0, leads through the resistance w to the movable contact arm d which is pro vided with an iron armature, and passes to the arm 9 which moves around P and which on account of its weight rests on the back bare ends of the auxiliary wires a of the first pair of carbons. These ends of the two auxiliary wires (1 are connected with each other. Therefore, it is possible to take,

instead of the two wires, one thicker wire or a plurality of thinner wires.

From the other pole the w1re g leads simultaneously to the lower carbons i of the same polarity. E-ach of these carbons i bears the wires a insulated along their length with silk, cot-ton, paper, enamel, aluminum oxid or. the like. Between the insulated wires a and the electrode 2' there is a thin layer of a mass 1) which is a conductor of high resistance and should be with difiiculty combustible. This mass 6 may be made of a paste which is obtained by mixing graphite and gy sum with a solution of gum-arabic or 0 water glass or the like. The specific resistance of this massmust be regulated by choosing the proportions of the substances employed according to the strength of the current used and the sectional'area of the wire a. In making the electrode the insulation of the wires (1 is scraped off or removed in any suitable manner to about 5 mm. in front that is to say, at the burning end of the electrode before the connection of -the electrode 2' with the wires a is effected, so that the" wires 0 which are embedded in the mass I) contact at their bare ends'with the resistance mass 1) which on the other side touches the electrodes 2' at their burning ends so that between the bare ends of the wires on and the electrode 2' a conducting connection is produced.

The wires a are also made bare at their back ends at o thatv is to say their insulation is also there removed. These bare ends 0 are wound firmly around the collar 7: which is of asbestos, so that the electrode 2', the mass 5, the wires a and the asbestos collar is form one 'firm piece. .The auxiliary current conductor 0 is connected by the arms d and g with the end 0 and is insulated from the electrode body 71 (by the asbestos collar k) Under the carbon three suitably formed supports n are arranged adjustably on an arm or rod m. Each of these supports n supportsone carbon with auxiliary wire.

If the circuit, leading to the lamp is closed, the current flows from 7 through the branching point 39 into the auxiliary wire 0, from this through the entire length of the auxiliary wire a and through the front bare end of the wire a into the resistance layer 6, through the entire length of the burning electrode 2' back into the wire g. This current, on the passage from the bare end of the Wire a into the carbons z' flows through the resistance mass and produces at this point Z a strong glow which rises to an explosion in a very short time, whereby 110 glowing particles and conducting vapors are shot out by the wire 0. and the mass 12, from the electrode i against the electrode 6, so that a conducting vapor bridge is produced between the electrodes, which results" 3. in the formation of an are, which on one side has its roots in Z and on the other side takes its roots in the nearest part of the electrode 6.

If the difierence the network and the arc-voltage is small, the amperage in the auxiliary circuit will decrease only a little after the arc is struck, as a simple calculation will show. In this case therefore it is necessary, to weaken or cut 125 cuit being connected in shunt to the are 136 between the voltage of that it crumbles falls in a relatively ver after the formation of t not absolutely necessary out the auxiliary current after the arc is struck. But even in the special case mentioned it is advantageous to cut out the auxiliary wire 0 as current is thereby saved and the quietness of the arc is favorably influenced. When the arc has been formed in the manner described, the current works in the usual manner, the electrodes 2' and e being consumed. With the consumption of the electrodes the front part of the wire a and of the resistance mass 6 also burn away in the same proportion as the electrode 2', as shown in Fig. 4. By the effect of the heat of the arc the front part a, of the insulation of the wire a is removed, that is to say is burnt up or crumbles away; on the other hand the heat of the arc also influences the front part b of the mass 1) in such a manner there and rests against the end of the wire a which has become bare, or embeds this bare end, so that there is a suflicient contact between the auxiliary wire a and the electrode 2' for forming the next arc. Each further striking of arc takes place in the manner above described. If the lamp is switched on and ofl a great number of times after each other, the place where the arc is formed naturally is removed gradually toward the back, as each time the arc is formed a little is burnt and exploded from the front end of the wire a and from the resistance mass 1). The are formed Will however always move forward and become fixed at the points of the electrodes 6 and i, because the electro-dynamic force which is formed by the loop; electrode e, are and electrode 2', drives it as a blowing magnet to the foremost ends of the electrodes e and 2', even if the arc were formed quite at the back, for instance at the hindmost end of the wire a in the vicinity of 0. This can take place when the lamp is being continually switched on and off without the electrodes being burned. Each following are then has its roots farther from the burning end of the electrodes, that is to say the places where the arc is formed are situated each time nearer the carbon holder until the wire a is burnt to the end and it is therefore no longer possible to form another are.

If the first pair of carbons is burnt away so far that the carbon z is no longer supported by its support a, it falls down, turning its holder 15 (Fig. 2) downward. In consequence. the arm 9 also loses the support which it had in the first carbon i and turns downward until it rests against the back bare end of the auxiliary wire a of the second lower carbon 2'. Thus the circuit of the second auxiliary wire a is closed;-the explosion between the carbons produces the arc L. The formation of the arc has the reimportant degree e arc, so that' it is in this case to cut sult that the iron core of the coil E becomes magnetic, it attracts the armature situated at the switch lever 01 together with (Z, and thereby the auxiliary circuit is broken. After the arc has been formed the glow lamps it connected in series with the coil E light up, which are arranged in place of a series resistance and can also be used for lighting.

If the current serving to ignite the arc is not stronger than what the glow lamps can bear, these glow lamps can be placed at any part of the network, for instance at the point S. If on the other hand a stronger current is temporarily used for igniting the arc, the glow lamps are placed at that part of the network which lies between the branching point p of the current and the electrodes c. This part of the network is not flowed through by the current until the arc is formed and is only then cut in if the arc" is formed. The glow lamps if they are arranged in this place can also be used if before the cutting in of the arc the current is considerably stronger than the usual working current.

The switching device now continues the work in the manner described, the third pair of carbons being lighted in the same manner as the second when the latter has burnt .out. To prevent the arm 9 from falling down with the remainder of the carbon and thus being damaged when the last pair of carbons is burnt up, a support A is provided which prevents the arm 9 from moving too far downward.

What I claim is:

l. The arrangement for forming an electrical arc, consisting of two electrodes which are conductors in the cold state, one being arranged in proximity to the other in the air, a current supply connected with said electrodes, a conducting substance which when heated emits conducting glowing particles and vapors, said substance being placed between said electrodes and insulated by an air space from one of the electrodes and coated with an insulation adapted to be consumed by heating, a conducting mass of high resistance connected with said substance, and means for passing a heating current through said electrodes and said conducting mass.

2. In the arrangement for forming an electrical arc, consisting of two solid electrodes which are conductors in the cold state,

one being arranged in proximity to the other i in the air, a current supply connected with said electrodes, a conducting substance which when heated emits conducting glowing particles and vapors, said substance being placed between said electrodes and insulated by an air space from one of the electrodes and coated with an insulation adapted to be consumed by heating, a conducting mass of high resistance connected with said substance, and means for passing a heating current through sald electrodes and said conducting mass, said heating current being put in shunt to the arc current and the Working current having a higher voltage than the arc.

3. In the arrangement for' forming an electrical arc, the combination of two solid electrodes which are conductors in the cold state, one being arranged in proximity to the other in the air, a current supply connected with said electrodes, a conducting substance which when heated emits conducting glowing particles and vapors, said substance being placed between said electrodes and insulated by an air space from one of the electrodes and coated with an insulation adapted to be consumed by heating, a conducting mass of high resistance connected with said substance, and means for passing a heating current through said electrodes and said conducting mass, said heating current being put in shunt to the arc current and the working current having a higher voltage than the arc, glow lamps being placed in the branch of the current which lies between the branch Wire leading to said substance and the electrode which is not connected with said substance.

In testimony whereof I have hereunto set my hand in presence of two subscribing Witnesses.

HENRY HAsPER, WoLnEMAR HAUPT. 

